Characteristics of the Gut Microbiota in Japanese Patients with Premenstrual Syndrome

PURPOSE: The present study aimed to characterize the gut microbiota of individuals with premenstrual syndrome. PATIENTS AND METHODS: The gut microbiota of 24 Japanese women with PMS (PMS group) and 144 healthy Japanese women (control group) were compared. Analysis of the α- and β-diversities and the gut microbial composition at the genus level were performed using 16S rRNA gene sequence data obtained from stool samples. RESULTS: A significant difference in age was observed between the PMS and control groups; however, no significant difference was observed in BMI. The α-diversity measured using the Simpson index was significantly higher in the PMS group than the control group. Visualization of the β-diversity using non-metric multidimensional scaling and permutational multivariate analysis of variance (PERMANOVA) showed that the distance of the gut microbiota between the PMS and control groups is significantly different. Furthermore, a significant difference in the composition of the gut microbiota was observed between the PMS and control groups. At the genus level, the abundances of Collinsella, Bifidobacterium, and Blautia were significantly higher in the PMS group than in the control group. In particular, the abundance of Collinsella in the PMS group was approximately 4.5 times higher than that in the control group. To rule out the confounding effect of age in the abundances of Bifidobacterium, Blautia, and Collinsella, the gut microbiota of the PMS and control groups were compared by age group. Results showed that Collinsella had the highest effect size in participants of 30–40 years of age (mean age: 36.39 ± 4.68 years). CONCLUSION: These results suggest that the PMS group possesses a characteristic gut microbiota. In particular, Collinsella was strongly associated with PMS. Since Collinsella has been reported to be associated with diet, dietary interventions such as prebiotics targeting Collinsella may be effective in preventing, improving, and alleviating PMS.